Gripping device



une 4 392, R. JoKscH 1,715,659

GRIPPING DEVICE Filed Feb; 2o. 1925 Patented June 4, 19.29'.v

UNITED 4STATES PATENT or-l=1`c1=..lu-

RUDOLF JOXBGH,A01I' AUSTRIA.

emrme DnvIc'r..

Application led February 20, 1925, Serial No. 10,714, and in ustrlav latch 1, 1924.

M invention relates to gripping devices of the d in which the'work piece is gripped along its whole contour at a plurality of points by means of movable jaws consisting of a pluralitty of individual gripping elements, each o which is capable to be pressed against said work piece, and it particularly relates to gripping devices of the kind mentioned in which the individual gripping elements are forming a movable wall of a chamber filled with a medium consisting of solid particles or of a solid but plastic material. It has for its object to arrange the parts in such a manner that individual adjustment of the gripping elements by virtue of the back pressure of the work piece is possible upon moving the jaws towards the work piece, whereby each gripping element will be capable to assume its position on the contour of the work piece to bel gripped by it, without being disturbed or influenced by the movement of any other gripping element of the jaw, while on the other 'hand-the pressure applied on the work piece by theelements'upon pressing the jaws towards the same will 'nevertheless be equally or practically equally distributed among all the individual elements, no device forv fixing the grl pmg elements in their gripping. position eing necessary and the adjustment and pressure distribution being performed quite automatically.

To obtain this result according to thisin-v vention the chamber which is enclosing the medium that is receiving the back pressure of the individual consists of soli particles such as steel balls or rollers or of a plastic or pulverulent material is only partly filled with such medium, thus allowin to utilize the property of such a medium to tke any form as long 'as suiiicient space is left into .which it may enter, but to act like a solid abutment when the medium is filling entirely said chamber and is'enclosed uniformly on all sides. It is thus ossible to allow individual adjustment of eac gripping element in lts correct position in good contact with the work piece at any polnt ofthe contour the individual element may happen to face Without being influenced bythe movement of any other individual gripping element, the medium behindthe gripping elements being capable to assume any form witliu said chamber behind said gripping eleviilcatio'ns of the invention.

gripping.

ipping element and which ments as long as a free spaceis left, while an equal pressure on all the gripping is exerted upon the ipping elements as soon as any free space 1n the chamber has disappeared, soV

that it will act 'as a solid bbdy sim ly transmltting the pressure from the blocl): pressed towards the work piece upon the grippingV4 elements proper.

.In order to restore the device into workingJ condition after having released the work piece a propelling device for the gripping elements either acting individually on each element or collectively on all elements must be thpace within the chamber is again entirely ed with said medium. 4 The invention is illustrated in the accompanymg drawings which show several modi- Fig. lof the drawing shows a gripping device, according to this invention in' longitudinal section.

Fig. 2 shows a iication.

vie-iisr of the same modi- Fig. 3 shows a erspective view of another modification of e invention, and

Fig'. 4 shows a section through this modi-5.

fcation.

In the device illustratedtwo movable jaws' are provided which consist of slidabl'e blocks 9, capable of being moved towards each other dle '8 provided with two opposite screw threads in the usual manner. These jaws are provided with suitable faces capable to slide Within a bed or a frame as usual. The supporting blocks are carrying a number of individual gripping elements 2 and are provided to this end with a frame 1, embracing and enclosing said gripping elements. The gippin elements are slidably mounted wit 'n sai frame 'which may be closed at the top as shown at 12 in Fig. 1.

The gri ping elements in this modification j las 2 of variable volume, said volume being infor gripping a work piece by means of a spinl 3 when it is extended so as to have its maximal volume by advancing the gripping elements towards the work piece but a free space is left for a purpose hereinafter described.

In this modification each gripping element is moreover provided withapropelling device,

which consists of a pin 6 arranged within .the block 9 underneath said element and a spring 7 which moves the pin away from the blocks.

The pins are supported within suitable bores 18 of the blocks 9 allowing to and fro movement of the pins. At its outer end each pin is provided with a head 19 abutting against a projection of the gripping element, thus pushing said grippingr element forward under the action of the spring when no back pressure is exerted upon it.

As already explained material do not fill entirely said chamber and -when therefore a work nece 'is inserted between the two opposing aces of the grippin elements, said elements can be ushed bac without appreciable resistance y the work piece ywhen the blocks are moved towards each v other by means of the screw 8. Each gripping element is pushed back according to tne width of said work piece at the point where the gripping element is applied.

The back'movement of each gripping element during the first period can practically be performed without resistance and independently of any movement of any other gripping elements as the medium filled in the chamber 3 will not be capable of transmitting any pressure from one element to the other or from the block to any element as long as free space is left within the chamber not filled by the me` dium 4. However this free space is reduced jaws towards each other and while this is done,

the grinning elements are thus taking theirv further pressure is applied, this medium will act likea rigid abutment and will therefore transmit the pressure from the blocks 9 and the bar 10 attached to -it to the gripping elements 1n the same way as if said gripping e1e work piece,

the particles of solid ments were in solid connection with the bar, and said pressure of the blocks 9 and the bar 10 will be uniformly acting upon all grippm elements which will ltherefore gri the wor piece along its whole contour wit umform or practically uniform pressure.

Thus the gripping elements are automatically adjusted by the back pressure ofthe work piece. during the gripping movement of the jaws and finally will grip the work piece firmly along its entire contour as soon as the medium 4 lls the entire space left within the chamber 3 when the back movement of the gripping elements has reached a certain extent. Whenever the screw 8 is moving the jaws 2 away from each other to release the the propelling devices 6, 7 will act upon the projections 5 of the grippin elements and willl move them again forwar so that the chamber 3 is extended. The device is then ready again for further operation.

The arrangement shown in Figs. 3 and 4 is practically the same as that Shown in Figs. 1 and 2, the difference residing only in the propelling device.

Instead of an individual propelling device for each gripping element, a common propelling device is arranged which consists of a bar 11 acting upon upwardly rotrudin extensions of the gripping eibments. his bar 11 is actuated by pins 16 which are spring tensioned and will try to push the bar forward, thus taking with it all the gripping elements which have been pushed back, thus restoring the initial working condition when the work piece has been taken away, in which event the volume of the chamber is restored to its ori inal extension, where the medium fills the c iamber only partly.

It is thus 'seen that the medium which is introduced into the chamber 3 performs the function of an abutment which, before acting as such is capable of adapting itself to any shape of the chamber formed partly by the ndlvidually movable gripping elements but uplon a corresponding movement of the jaws w en the space within the chamber is entirely filled will forma rigid abutment allowing `press-ure to be transmitted from the blocks to the grippin elements actin like a solid t more and more as the spindle 8 is movingI the b d g g I claim: A 1. A gripping device comprising movable jaws composed of individually movable ripplng elements and a carrier block there or, a chamber formed by portions of said grip ing elements and of said carrier block,fa me ium 1n said chamber capable of adapting itself to all shapes of said chamber acting as a ri abutment, and means moving said gripplng elements out of said chamber to a common almement. 2. A gr1pp1ng device comprising movable jaws composed of individually movable gripping elements and a carrier block therefor, a. by returning all said gripping elements to a chamber formed by portions of said gripnormal position. ping elements and of said carrier block, a me- 3. A gripping device as specified in claim dium in said'chamber capable of adapting itself to all shapes of said chamber, acting as a rigid abutment for transmitting pressure and a common means adapted to move al1 gripping elements out of said chamber theretrolled bar adapted to bear upon some portion of said gripping elements. p

In testimony whereof I aiiix my signature.

RUDOLF J OKSCH.

2 vin which said means consists of a spring con'- 

